The European Union said on Sunday it was suspending further work with Ukraine on an ambitious trade and cooperation agreement because the government in Kiev had failed to give a clear commitment to signing the deal.

EU enlargement chief Stefan Fuele said on Twitter that the words and deeds of Ukrainian President Viktor Yanukovich and his government on the proposed trade pact with the EU were "further and further apart. Their arguments have no grounds in reality."

Fuele said he had told Ukraine's first deputy prime minister Serhiy Arbuzov in Brussels last Thursday that further discussion on the trade agreement was conditional on a clear commitment by Kiev to sign it, but he had received no response.

As a result, work on the agreement was "on hold", he said.

Kiev had been expected to sign the agreement at a summit last month, but Yanukovich turned his back on the accord at the last minute in favour of closer ties with Moscow, leading to mass protests in Kiev.

The EU kept its offer on the table and Arbuzov said in Brussels last Thursday that Ukraine would sign the pact soon, but Brussels disputes Kiev's assertions that it needs 20 billion euros ($27 billion) of EU aid to offset the cost of adapting to the agreement.